Rumen physiology

Question 1

define rumen

Answer 1

the large first stomach of a ruminant, in which cellulose is broken down by the action of symbiotic microorganisms

Question 2

define mutualistic symbiosis

Answer 2

mutually beneficial interactions between two species

Question 3

give an example of mutualism between vertebrates and bacteria

Answer 3

vertebrates lack cellulase enzyme, which digest cellulose, but microbes possess them so herbivores utilize fermentation by microbial gut populations for energy

Question 4

what increase the surface area of rumen

Answer 4

papillae - finger like projections

Question 5

what are papillae

Answer 5

finger like projections that increase surface area of rumen

Question 6

what is the reticulorumen

Answer 6

• represents one functional space
• first site for microbial fermentation of ingested feed
• retention of long forage particles in fibrous mat stimulate rumination

Question 7

what is ruminal fermentation

Answer 7

extensive pre-digestive and pre-absorptive microbial fermentation

Question 8

what are some positives of ruminal fermentation

Answer 8

• utilisation of fibrous feeds
• utilisation of lower quality N sources
• production of water-soluble vitamins and vitamin K

Question 9

negatives of ruminal fermentation

Answer 9

• reduced utilisation with higher quality feeds
• reduced yield from digestible energy sources

Question 10

how do cows release methane

Answer 10

through eructation (belches)

not farts